Field
The field relates to apparatus and methods for packaging, and in particular, to apparatus and methods for packaging stress-sensitive device dies.
Description of the Related Art
Electronic devices often include packages that have one or more integrated device dies that are sensitive to stresses induced during manufacturing, assembly, transportation, and/or use. Stresses may cause the device die to warp and/or may damage components formed in or on the die. In some cases, when an encapsulant or molding material is applied over a die, the moisture content and material properties of the encapsulant can change throughout the life of the package. Changing moisture content can cause the encapsulant to swell or otherwise deform, which can damage the integrated device die or change the stresses experienced by the die over its working life. Similarly, changing temperature can change the material properties of the encapsulant which can impart stresses on the die surface. For example, various types of microelectromechanical systems (MEMS) dies may include components that are sensitive to such stresses. In some arrangements, a MEMS accelerometer die or a MEMS pressure sensor die may include various mechanical components, such as beams, that may be damaged if subjected to sufficiently high stresses. In other examples, dies with absolute outputs, such as voltage reference circuits, can be sensitive to the stresses of encapsulants. Also, dies used for various types of precision amplifier, reference or converter products may be also be susceptible to encapsulant stresses. Accordingly, there is a continuing need for improved packaging arrangements for stress-sensitive device dies.